Polaris GAS WATER HEATER Installation, Operation And Service Manual page 12

HORIZONTAL DIRECT VENT TERMINAL
INSTALLATIONS
STD. HORIZONTAL TERMINATION
When 3 in. pipe is used between the water heater and the outside wall,
reduce it to 2 in. pipe before penetrating the wall. A maximum of 18
inches of 2 in. pipe may be used.
The standard horizontal inlet air termination is a 2 in. pipe which
terminates at the exterior wall and utilizes a coupling to prevent the pipe
from being pushed back into the structure. The standard horizontal
exhaust outlet termination is a 2 in. pipe which terminates 12 inches
from the outside wall. See Figure 9 for the proper minimum termination
clearances. The air inlet must be located with respect to the exhaust
outlet as shown in Figure 10.
Install a 2 in. coupling at the
outside wall on both the inlet and
exhaust to prevent the
terminations from being pushed
inward.
Install a drain tee assembly and
trap as close to the water heater
as possible. This is to drain any
water that may be in the
combustion air pipe and prevent it
from entering the inducer blower.
Connect the trap drain line to a
suitable drain or to the
downstream of the condensate
trap of the water heater. Do not
terminate the trap drain line
into the condensate drain vent
ALT. HORIZONTAL
TERMINATION
The combustion air and exhaust terminations may be raised
up to 24 inches above the wall penetrations if required for
anticipated snow levels. See Figure 11. The two elbows
shown in Figure 11 are considered part of the termination and
should not be included when determining the maximum
allowable vent pipe length.
SEE PAGE 30 FOR ALTERNATE AIR INLET DRAIN TEE
ASSEMBLY CONFIGURATION.
12
EXHAUST AND INLET AIR PIPING (CONT.)